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Reason for index corruption?
Message
 
 
To
18/09/2006 09:26:21
General information
Forum:
Visual FoxPro
Category:
Databases,Tables, Views, Indexing and SQL syntax
Environment versions
Visual FoxPro:
VFP 9 SP1
OS:
Windows XP SP2
Network:
Novell 4.x
Database:
Visual FoxPro
Miscellaneous
Thread ID:
01154622
Message ID:
01154654
Views:
24
>>>
>>>Yes.
>>>Someone turns off workstation without proper shutdown.
>>
>>I have often heard the above explanation for the index corruption. But I am wondering, if a table is open by the application but the application is idle, would it still corrupt an index? And why?
>
>Any indexed field may have been updated but the updated DBF and/or CDX (the .cdx file may be updated "later" for all I know) records are still in the OS cache and have not been transferred to the real table.
>Keep in mind that that FLUSH without the new VFP9 parameter simply tells the OS that the application is finished with the record. It does NOT ensure that the record is immediately written to the actual table.
>Depending on how VFP handles .CDX files it could be even worse for them.
>
>That's one theory.

I didn't know about the new parameter FLUSH has in VFP 9. I will look it up. It seems to me that forcing the application to write the data to the .dbf and .cdx table should minimize corruption a great deal. Because it seems to me that if the data is physically written to the .dbf and .cdx, turning off a pc should have no effect on the index or table corruption.
"The creative process is nothing but a series of crises." Isaac Bashevis Singer
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